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10 Ways To Secure a Window Air Conditioner From Theft

Air conditioners are essential in keeping your home cool and comfortable. They help reduce humidity, circulate and filter air and remove pollutants, thus enhancing your safety and quality of life. To maintain these and other benefits, you need to keep your window air conditioner secure.

Here are 9 tips on how to secure a window air conditioner from theft:

  1. Burglar-proof your window.
  2. Mount the window AC unit securely.
  3. Extend the accordion panels. 
  4. Use an AC cage.
  5. Install security bars.
  6. Fix motion-detecting lights near the window unit.
  7. Install a home security system.
  8. Carefully consider the placement of your window AC unit.
  9. Keep a close check on your vacant property.

Read on to learn some valuable ways to keep your window AC safe from theft, falling out, or getting pushed out the window.


1. Burglar-Proof Your Window

Gaining entrance into a home with a window air conditioning unit is relatively easy since the window remains primarily open. However, sealing the window can help prevent a burglar from easily pulling the AC out. 

Burglars typically look for quick and easy entry. Therefore, if your window fails to budge after giving it a hard push, a thief will most likely give up and move on.

Here are practical ways to keep your window unit safe:

  • Add window locks. Installing sliding locks like this Prime Line Vinyl Window Lock (available on Amazon) on either side of the frame can keep an intruder from forcing your window up or down. Sliding window locks are easy to install, don’t require installation tools, and are fairly affordable.
  • Prevent the window from sliding up or down. Use a piece of wood to hold the window in place, stopping it from being raised from the outside.
  • Install a sensor alarm. Get a window sensor alarm and set it up at the window holding the AC unit in place. If someone pushes the window up or tries to dislodge the AC, the alarm will go off, scaring them away.
  • Buy a security lock. Use an AC security lock to help keep a window unit placed on upper floor windows safe. 
  • Install flaps. Getting your window unit to fit properly means installing a unit that’s smaller than your window. Unfortunately, the space surrounding the unit makes the window vulnerable to break-ins. To secure the area, install metal or plastic flaps over the open spaces.
  • Make the window unit less accessible: Consider making your window unit less accessible by planting shrubbery next to the window. Make sure the shrubbery obstructs an intruder’s view of the AC or makes it more challenging for them to get near the window and steal it. Rose bushes are a great option here.

Watch this short video to learn how to burglar-proof your window air conditioner:

2. Mount the Window AC Unit Securely

Some homeowners rely on the windowsill alone or gravity to keep their air conditioning unit in place. This is a mistake. Securing the AC properly can help prevent your unit from accidentally falling out the window. Mount the AC to the window sash, then screw down the unit on the top, sides, and bottom. This will not only secure your AC but will also make it harder for a thief to steal it or break into the house.

Additionally, consider purchasing a proper window air conditioner bracket like this window air conditioner bracket. Installing a bracket on the unit’s exterior will support the AC, making it more difficult to get it out of the way. The bracket also makes it harder to remove the AC from the outside.

Corner braces are also useful when installing your window unit. Like the brackets, they provide your window unit with extra support and keep the AC securely in place, preventing it from being pushed out of the frame.

3. Extend the Accordion Panels

Most window AC units come with accordion panels found on either side of the unit. When installing your window AC, be sure to extend these panels as wide as they can go. Doing so helps get rid of any areas a thief can use to snatch the unit out of the window. 

Extending accordion panels will slow down a burglar, but you might want to enhance your security by replacing the plastic accordion panels with wooden ones.

4. Use an AC Cage

Consider placing your air conditioning unit in a cage. While this might not be aesthetically appealing, it’ll protect your window unit from theft. Besides, the cage only covers the AC’s exterior; hence won’t affect your window aesthetics much.

An air conditioning cage is effective because it makes it extremely difficult for a burglar to steal your AC. This is because the cage’s metal bars prevent a thief from reaching in and grabbing the unit. Furthermore, hacking into a metal cage takes time and effort, heightening the chances of getting caught; this is enough to deter petty burglars.

Securing your AC in this manner also enhances safety; it prevents the AC from getting dislodged easily in a storm or falling and hitting someone.

5. Install Security Bars

Another option is to install adjustable window security bars like this security bar. These bars typically slide into place at various points around the window, helping to lock in place either the window or AC unit, or both. They’re specially built to fit in the space between the window and upper frame, preventing the window from opening beyond a certain adjustable opening distance.

For best results, measure the gap to ensure you purchase a correctly-sized security bar.

6. Fix Motion-Detecting Lights Near the Window Unit

Prevent criminal elements from tampering with your window air conditioner by fixing motion-detecting lights In the area surrounding the window unit. Most petty thieves will scamper off if you expose their criminal acts using bright lights.

7. Install a Home Security System

Consider installing a home security system in addition to the window sensor alarm. A survey conducted by the University of North Carolina reported that 60% of convicted burglars avoided breaking into homes with visible signs of surveillance equipment. These included stickers or visible alarms and cameras. The burglars also confessed to gaining entry into the vandalized homes through open windows or by forcing windows open.

Professionally-installed home security systems are the best because they keep your entire property safe from intruders and warn the authorities in case of a break-in. Furthermore, you can set up your sensor alarm to trigger the security system if a thief attempts to dislodge the window air conditioner. 

Be sure to put a home security sticker next to any windows housing an AC unit. For extra security, consider getting a dog to keep your home safe from intruders, and don’t forget to always keep the gate locked. The goal here is to make potential burglars reconsider their plan to steal your window air conditioning unit.

8. Carefully Consider the Placement of Your Window AC Unit

A window unit placed on the first-floor window is particularly attractive to burglars, as it’s fairly easy to push in an unsecured unit to jump in and steal other valuables. If possible, avoid installing your window unit on the first floor of your apartment and go for the second floor instead. If this isn’t an option, consider using the unit seasonally and shifting it during colder months.

Some people prefer locating their window AC within a clear view. An example of this is placing it facing a street with regular traffic. This deters potential thieves, as passers-by or people driving past your home would easily spot them.

9. Keep a Close Check on Your Vacant Property

If you have a vacant property, keep checking on it regularly. With the increasing cases of AC burglaries, local authorities encourage homeowners and business owners to monitor their properties closely and, if possible, fence the area surrounding their window units. It’s also recommended to use motion light detectors to deter would-be burglars.

Homeowners with properties located on rural roads with few neighbors or passing traffic also need to be extra cautious, as criminals can easily abscond with their window ACs.

10. How To Secure a Window AC Unit Without Screws

An improperly installed window AC poses a significant safety risk. The unit could fall off the window, causing anyone passing beneath the window grievous harm. But how do you secure your window AC unit without using screws? This is particularly important if your window frames are wooden and you don’t want them to get damaged. 

The best way to secure your window unit is by using a window unit supporting bracket. You only need to hook the bracket to the inner side of your window sill, leaving gravity to do the rest of the work. Note, however, the unit might contain screws that require tensioning. 

Fortunately, most support brackets don’t need drilling or screws during installation. A good example is this air conditioner support bracket. This bracket features an expandable bar and two feet with rubber tips. The bar firmly fits in the lower window frame while the feet rest against the outer wall, supporting the AC’s weight.

The great thing about support brackets is they’re versatile and can work with all types of building material. As such, you can use them on concrete, wood, or brick. They’re also ideal for securing AC units without flat bottoms. 

While a properly installed window unit can sit securely without a support bracket, heavy units require additional support. Moreover, this might be a standard requirement in places like New York City.

Another helpful option is using the sliding locks discussed earlier. These add an extra layer of security to your window and don’t require screws. 

Helpful Tips When Installing Your Window AC Without Screws

Proper AC installation allows your unit to run efficiently for longer, minimizing the need to replace essential components. Ultimately, this saves you money. Here are some handy tips to bear in mind when installing your window unit without screws:

  • Ask about laws on installation and support in your locality; some jurisdictions might insist on adding extra support for your AC. 
  • Ensure you connect power appropriately to avoid a malfunction or fire hazard.
  • Only open the window housing of the AC unit during a scheduled service.
  • Avoid using loose objects to support your window unit since this creates a great risk of the AC unit falling.
  • For maximum safety and to avoid causing damage to your window, have someone assist you during the installation.

Watch how to install your window air conditioning unit safely without using screws or drilling holes in the below video:

How Do You Secure the Side of an Air Conditioner?

You can secure the sides of your window air conditioner by screwing the side panels to the window sill or frame. Alternatively, you could choose to screw the AC’s top mounting rail to the window sash. 

If possible, try to drill more holes through the top mounting rail to allow for additional screws on the lower window sash.

Most window ACs also come equipped with small metal brackets to screw in for extra security. 

Why Would Someone Steal an AC Unit?


Someone would steal an AC Unit because the copper used in manufacturing them fetches high prices. As a result, criminals remove the metal from the AC unit and sell it on the black market. Alternatively, they take the copper to a scrap yard and exchange it for money.

While some of the thieves strip your window unit off its copper heat-exchange coils, others take off with the entire unit, causing costly damage. 

Final Thoughts

A window air conditioner is appealing to burglars because it’s usually easier to steal while also providing effortless entry into your home. Keeping your home safe from burglars is vital for your safety, protecting your property, as well as ensuring your peace of mind. 

To secure your unit from theft or stop it from accidentally smashing to the ground, take the necessary precautions by following the helpful suggestions shared in this article. Ultimately, the security measures you employ to secure your air conditioning unit will depend on the type of AC, its placement, your window, plus overall security arrangements.

For more, check out How to Install a Security Camera on Vinyl Siding | 6 Easy Steps.